package com.atguigu.gulimall.seckill.service.impl;

import com.alibaba.csp.sentinel.Entry;
import com.alibaba.csp.sentinel.SphU;
import com.alibaba.csp.sentinel.annotation.SentinelResource;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.atguigu.common.to.mq.SeckillOrderTo;
import com.atguigu.common.utils.R;
import com.atguigu.common.vo.MemberRespVo;
import com.atguigu.gulimall.seckill.feign.CouponFeignService;
import com.atguigu.gulimall.seckill.feign.ProductFeignService;
import com.atguigu.gulimall.seckill.interceptor.LoginUserInterceptor;
import com.atguigu.gulimall.seckill.service.SeckillService;
import com.atguigu.gulimall.seckill.to.SeckillSkuRedisTo;
import com.atguigu.gulimall.seckill.vo.SeckillSessionsWithSkus;
import com.atguigu.gulimall.seckill.vo.SkuInfoVo;
import com.baomidou.mybatisplus.core.toolkit.IdWorker;
import javafx.scene.control.TableColumnBase;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RSemaphore;
import org.redisson.api.RedissonClient;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.BoundHashOperations;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;

import java.util.*;
import java.util.concurrent.TimeUnit;
import java.util.regex.Pattern;
import java.util.stream.Collectors;

@Slf4j
@Service
public class SeckillServiceImpl implements SeckillService {

    @Autowired
    CouponFeignService couponFeignService;

    @Autowired
    StringRedisTemplate redisTemplate;

    @Autowired
    RabbitTemplate rabbitTemplate;


    private final String SESSIONS_CACHE_PREFIX="seckill:sessions:";
    private final String SKUKILL_CACHE_PREFIX="seckill:skus:";
    private final String SKU_STOCK_SEMAPHORE="seckill:stock:";//+商品随机码

    @Override
    public void uploadSeckillSkuLatest3Days() {
        //扫描最近3天需要秒杀的活动
        R session = couponFeignService.getLatest3DaySession();
        if (session.getCode()==0){
            //上架商品
            List<SeckillSessionsWithSkus> sessionData = (List<SeckillSessionsWithSkus>) session.getData(new TypeReference<List<SeckillSessionsWithSkus>>() {
            });
            if (!CollectionUtils.isEmpty(sessionData)){
                //缓存到redis
                //1 缓存活动信息
                saveSessionInfos(sessionData);
                //2缓存活动关联的商品信息
                saveSessionSkuInfos(sessionData);
            }
        }

    }

    public List<SeckillSkuRedisTo> blockHandler(BlockException e){
        log.error("getCurrentSeckillSkusResource被限流了。。。");
        return null;
    }

    /**
     * 当前时间参加秒杀的商品信息
     * @return
     */
    @SentinelResource(value = "getCurrentSeckillSkusResource",blockHandler = "blockHandler")
    @Override
    public List<SeckillSkuRedisTo> getCurrentSeckillSkus() {
        //1 确定当前时间属于哪个秒杀场次
        //1970
        long time = new Date().getTime();
        try(Entry entry = SphU.entry("seckillSkus")){
            Set<String> keys = redisTemplate.keys(SESSIONS_CACHE_PREFIX + "*");
            for (String key : keys) {
                //seckill:sessions:1698019200000_1698026400000
                String replace = key.replace(SESSIONS_CACHE_PREFIX, "");
                String[] s = replace.split("_");
                long start = Long.parseLong(s[0]);
                long end = Long.parseLong(s[1]);
                if (time>=start&&time<=end) {
                    //2 获取这个秒杀场次需要的所有商品信息
                    List<String> range = redisTemplate.opsForList().range(key, -100, 100);
                    BoundHashOperations<String, String, String> hashOps = redisTemplate.boundHashOps(SKUKILL_CACHE_PREFIX);
                    List<String> list = hashOps.multiGet(range);
                    if (list!=null) {
                        List<SeckillSkuRedisTo> collect = list.stream().map(item -> {
                            SeckillSkuRedisTo redisTo = JSON.parseObject((String) item, SeckillSkuRedisTo.class);
                            return redisTo;
                        }).collect(Collectors.toList());
                        return collect;
                    }
                    break;
                }
            }
        } catch (BlockException e) {
            log.error("资源被限流,{}",e.getMessage());
        }


        return null;
    }

    @Override
    public SeckillSkuRedisTo getSkuSeckillInfo(Long skuId) {
        //找到所有需要参与秒杀的商品的key
        BoundHashOperations<String, String, String> hashOps = redisTemplate.boundHashOps(SKUKILL_CACHE_PREFIX);
        Set<String> keys = hashOps.keys();
        if (keys!=null&&keys.size()>0) {
            String regx = "\\d_" + skuId;
            for (String key : keys) {
                //6_4
                if (Pattern.matches(regx, key)) {
                    String json = hashOps.get(key);
                    SeckillSkuRedisTo skuRedisTo = JSON.parseObject(json, SeckillSkuRedisTo.class);
                    //随机码
                    long current = new Date().getTime();
                    if (current>=skuRedisTo.getStartTime()&&current<=skuRedisTo.getEndTime()){
                    }else{
                        skuRedisTo.setRandomCode(null);
                    }
                    return skuRedisTo;
                }
            }
        }
        return null;
    }

    @Override
    public String kill(String killId, String key, Integer num) throws InterruptedException {
        MemberRespVo respVo = LoginUserInterceptor.loginUser.get();
        //获取当前秒杀产品的详细信息
        BoundHashOperations<String, String, String> hashOps = redisTemplate.boundHashOps(SKUKILL_CACHE_PREFIX);
        String json = hashOps.get(killId);
        if (StringUtils.isEmpty(json)){
            return null;
        }else{
            SeckillSkuRedisTo redis = JSON.parseObject(json, SeckillSkuRedisTo.class);
            //校验合法性
            Long startTime = redis.getStartTime();
            Long endTime = redis.getEndTime();
            long ttl = endTime - startTime;
            long time = new Date().getTime();
            if (time>=startTime&&time<=endTime){
                //2 校验随机码和商品id
                String randomCode = redis.getRandomCode();
                String skuId =redis.getPromotionSessionId()+"_"+redis.getSkuId();
                if (randomCode.equals(key)&&skuId.equals(skuId)){
                    //3 购物数量
                    Integer seckillLimit = redis.getSeckillLimit();
                    if (num<=seckillLimit){
                        // 4 验证是否买过 幂等性，如果只要秒杀成功，就去站位 userId_SessionId_skuId
                        String redisKey=respVo.getId()+"_"+skuId;
                        //自动过期
                        Boolean aBoolean = redisTemplate.opsForValue().setIfAbsent(redisKey,num.toString(),ttl, TimeUnit.MICROSECONDS);
                        if (aBoolean){
                            //未买过，站位成功
                            RSemaphore semaphore = redissonClient.getSemaphore(SKU_STOCK_SEMAPHORE + randomCode);
                            boolean b = semaphore.tryAcquire(num, 100, TimeUnit.MILLISECONDS);
                            if (b){
                                //秒杀成功
                                //快速下单 发送mq消息 10ms
                                String timeId = IdWorker.getTimeId();
                                SeckillOrderTo orderTo = new SeckillOrderTo();
                                orderTo.setOrderSn(timeId);
                                orderTo.setMemberId(respVo.getId());
                                orderTo.setNum(num);
                                orderTo.setPromotionSessionId(redis.getPromotionSessionId());
                                orderTo.setSkuId(redis.getSkuId());
                                orderTo.setSeckillPrice(redis.getSeckillPrice());
                                rabbitTemplate.convertAndSend("order-event-exchange","order.seckill.order",orderTo);
                                return timeId;
                            }else{
                                return null;
                            }
                        }else{
                            return null;
                        }
                    }

                }else{
                    return null;
                }


            }else {
                return null;
            }



        }

        return null;
    }

    private void saveSessionInfos(List<SeckillSessionsWithSkus> sessions){
        sessions.stream().forEach(session->{
            long startTime = session.getStartTime().getTime();
            long endTime = session.getEndTime().getTime();
            String key=SESSIONS_CACHE_PREFIX+startTime+"_"+endTime;
            Boolean hasKey = redisTemplate.hasKey(key);
            if (!hasKey) {
                List<String> collect = session.getRelationSkus().stream().map(item ->item.getPromotionSessionId()+"_"+ item.getSkuId().toString()).collect(Collectors.toList());
                //缓存活动信息
                redisTemplate.opsForList().leftPushAll(key,collect);
            }
        });


    }

    @Autowired
    ProductFeignService productFeignService;

    @Autowired
    RedissonClient redissonClient;


    private void saveSessionSkuInfos(List<SeckillSessionsWithSkus> sessions){
        sessions.stream().forEach(session->{
            //准备hash操作
            BoundHashOperations<String, Object, Object> ops = redisTemplate.boundHashOps(SKUKILL_CACHE_PREFIX);
            session.getRelationSkus().stream().forEach(seckillSkuVo -> {

                //4 随机码 seckill?skuId=1&key=asdfghg
                String token = UUID.randomUUID().toString().replace("-", "");
                if (!ops.hasKey(seckillSkuVo.getPromotionSessionId()+"_"+seckillSkuVo.getSkuId().toString())) {
                    //缓存商品
                    SeckillSkuRedisTo redisTo = new SeckillSkuRedisTo();
                    //1 sku的基本信息
                    R skuInfo = productFeignService.getSkuInfo(seckillSkuVo.getSkuId());
                    if (skuInfo.getCode()==0) {
                        SkuInfoVo info = (SkuInfoVo) skuInfo.getData("skuInfo", new TypeReference<SkuInfoVo>(){});
                        redisTo.setSkuInfo(info);
                    }
                    //2 sku秒杀信息
                    BeanUtils.copyProperties(seckillSkuVo,redisTo);
                    //3 设置当前商品秒杀的时间信息
                    redisTo.setStartTime(session.getStartTime().getTime());
                    redisTo.setEndTime(session.getEndTime().getTime());

                    redisTo.setRandomCode(token);
                    String jsonString = JSON.toJSONString(redisTo);
                    ops.put(seckillSkuVo.getPromotionSessionId()+"_"+seckillSkuVo.getSkuId().toString(),jsonString);

                    //如果当前这个场次的商品的库存信息已经上架就不需要再上架
                    //使用库存作为分布式信号量 限流
                    RSemaphore semaphore = redissonClient.getSemaphore(SKU_STOCK_SEMAPHORE + token);
                    //商品可以秒杀的数量作为信号量
                    semaphore.trySetPermits(seckillSkuVo.getSeckillCount());
                }

            });


        });
    }
}
